Optical lenses are employed in a variety of devices for many purposes such as modifying focus and magnification. Many conventional devices that employ optical lenses use lenses that are made from solid materials, such that the optical properties of the lenses (e.g., their focal distances) remain constant or nearly constant over time. For example, cameras and other optical systems such as microscopes, video monitors, video recorders, copy machines, and scanners commonly employ solid lenses.
The use of solid lenses with fixed optical properties entails disadvantages in systems that employ combinations of lenses that interact with one another to provide overall optical properties. Such systems include, for example, zoom and focus lens systems in which two or more optical lenses of fixed optical properties are moved relative to one another to change optical properties of the overall combination of lenses forming the zoom and focus lens. Because the optical properties of the individual lenses used in such systems are fixed, the overall optical properties of the combinations of lenses depend upon other factors, particularly the relative positioning of the individual lenses. Consequently, to provide the desirable features and capabilities associated with systems such as zoom and focus lens systems, complicated and expensive mechanical and/or other components and techniques must be employed to achieve the desired effects.
In particular, conventional systems with zooming and focusing capabilities are typically more expensive and often more bulky than systems without such capabilities. Currently, all optical zoom and focus lenses achieve zoom-in, zoom-out and focus functions by changing the distance(s) between the individual lenses forming the overall zoom and focus lens. This involves high-precision mechanical motions of the lenses over a typical range of several centimeters. To provide highly-precise, reliable relative movement of the lenses typically requires a mechanical system that is complicated, slow, bulky and expensive.
The need to vary lens distance to achieve zooming and focusing has become a roadblock for incorporating zooming features into many new and emerging applications. Many modern “electronic gadgets” including cell phones, personal digital assistants (PDAs), and notebook computers are equipped with CCD or CMOS cameras. Implementation of cameras into such gadgets has evolved from being a novelty to being a standard feature, and many such gadgets now support imaging-related functions that involve not just imaging but also recording, videophone capabilities, and video conferencing. Yet conventional zoom and focus lenses are difficult to incorporate into these small electronic gadgets and their optical devices.